IT’S DISAPPOINTING that federal prosecutors in Savannah have decided not to file criminal charges against operators of the Imperial Sugar refinery in Port Wentworth, site of a massive explosion and fire in 2008 that killed 14 employees.

Federal safety officials had concluded that “willful” violations of rules that protect workers’ lives occurred at the riverside plant, which became a death trap after sugar dust ignited inside facility. They also found that the catastrophe was “entirely preventable.”

Yet Edward J. Tarver, U.S. Attorney for the Southern District of Georgia, seemed to disagree with the federal government’s own findings.

“There was insufficient evidence of intentional disregard or plain indifference to the requirements of OSHA’s general housekeeping standards to charge Imperial Sugar with a criminal violation,” Mr. Tarver said in a news release that split the narrowest of hairs.

Then, he continued to subdivide more follicles. He declared that his decision to sit on the sidelines was based in the lack of laws “specifically addressed to the safety of workers within the sugar industry at the time of the Imperial Sugar explosion.”

Mr. Graham, who was vice president of Imperial’s operations at that time, told a U.S. Senate panel that he warned the company’s CEO John Sheptor and managers at the company’s Port Wentworth and Gramercy, La., refineries that their plants were riddled with safety hazards. He said he listed about 400 safety hazards during a five-day walk-through. That included potentially explosive sugar dust that was ankle-, knee- and waist-deep in places, fire hoses that were rotting, fire extinguishers that had not been checked as required and employees that could not recall the last time they had participated in a fire drill.

And what was the boss’ response? Mr. Graham said he was scolded for being “excessively eager in addressing the refinery’s problems.” He also said he advocated closing down the plant for cleaning, adding that “I told Mr. Sheptor I was surprised we hadn’t killed anybody already because the plant was so dangerous.”

That explains why the U.S. Occupational Health and Safety Administration hit Imperial Sugar with charges of “willful” violations of workplace safety rules. Explosive dust doesn’t accidentally accumulate to snow-drift-sized piles. Fire hoses riddled with dry rot can’t fix themselves. Someone decided that it wasn’t important to check fire extinguishers or hold fire drills in a place where a single spark could blow the roof off — and did.

These may be considered mere “housekeeping violations” that merit misdemeanor offenses, as opposed to felony charges. But that doesn’t excuse looking the other way when 14 people are dead.

There’s an old saying that’s tried and true: The buck stops here. The buck for the Feb. 7, 2008, accident that the U.S. Chemical Safety Board declared “entirely preventable” stopped on the desk of corporate honchos in Sugar Land, Texas, where Imperial Sugar was headquartered.

Mr. Tarver said he lacked sufficient evidence of intentional disregard or plain indifference. Yet a high-level, corporate whistleblower was already on the record, suggesting exactly that. This just doesn’t add up.

Imperial has paid a $4 million fine. Until Tuesday, the only question was whether company execs would have to do more than write a check for this industrial nightmare.

Federal prosecutors have tremendous discretion in deciding which cases they take to grand juries. Some are like slam dunks in gaining convictions. Others may be 50-50. Or less.

But sometimes, prosecutions serve a healthy purpose — win or lose. They send a message that the federal government will hold people accountable for their behavior, which the public often needs to hear.

Contrast Mr. Tarver’s decision with the clear, no-nonsense action of his counterpart in Macon, Michael J. Moore, U.S. Attorney for the Middle District of Georgia.

Last week, a grand jury in Middle Georgia returned a 76-count indictment against four former peanut company officials connected to a Georgia peanut plant, which was linked to a 2009 salmonella outbreak that killed nine people. That plant suffered from atrocious housekeeping, too.

Mr. Moore may not win that case. But it served as a healthy warning to food manufacturers who may compromise consumer safety in search of higher profits.

Mr. Tarver has a good reputation and some excellent prosecutors. That’s why Tuesday’s decision is more than disappointing. It’s baffling.

“You can’t count on the U.S. Attorney’s office,” said Bart Turner, a Savannah trial lawyer who represents several people who are suing Imperial.

No kidding.

This is one time when the Justice Department — as opposed to justice — was blind.